One vertex per element, one color per generator, with an edge from x to x·s.
(2,4)(5,6)(7,14)(8,12)(9,18)(10,13)(11,17)(15,20)(16,19)(21,22,25,28)(23,30,24,27)(26,29,32,35)(31,36,33,34)(5,7)(6,11)(8,15)(9,16)(10,17)(12,19)(13,14)(18,20)(23,31)(24,33)(26,32)(27,34)(29,35)(30,36) involution — undirected(1,2,3,4)(5,8,10,9)(6,12,13,18)(7,15,17,16)(11,19,14,20)(21,23,26,31,25,24,32,33)(22,27,29,34,28,30,35,36)(5,9,10,8)(6,12,13,18)(7,16,17,15)(11,19,14,20)(23,24)(27,30)(31,33)(34,36)(7,17)(11,14)(15,16)(19,20)(21,24,26,33,25,23,32,31)(22,27,29,34,28,30,35,36)A Cayley diagram is a choice, not a fact about the group. Another drawing of this group — in a book, or on a different generating set — may look nothing like this one.